unfortunate and ultimately pointless debate rages between those who
find the scientific basis of evolution compelling, and those who choose
not to believe on religious 
and religion inhabit two very different worlds, demanding neither reconciliation
or supremacy. Science values proof before faith, while religion values
faith before proof. Indeed, God bestows his greatest blessings on those
who trust in his existence without the benefit of miracles or peer pressure.
Ironically, creationist attempts to overturn Darwinism on "technical
grounds" undermines the very foundations of religion, and are ultimately
self-defeating. For if God's existence is a necessary precondition for
"Intelligent Design" to make sense, then God's non-existence
is a logical consequence of the blatant failures of creationism to explain
anything but the prejudices of its proponents.
despite all the noise and emotions, both scientists and creationists
agree on almost all aspects of Darwin's great discovery- reducing the
debate to one small, but important point. And that is the subject of
Darwin's Law  of Evolution
by Natural Selection (traditionally referred to as a "theory"
to honor Darwin's original treatise, but now confirmed through observation
and experiment) consists of four main tenets. First, he describes how
species can change in shape and character through selective breeding.
No reasonable person, whether creationist or scientist, doubts selective
breeding can morph a wolf into a pony-sized mastiff. Or evolve the same
wild animal into a comically shrunk, rat-sized Chihuahua. Second, he
describes how species are neither completely uniform nor immutable,
and how these natural variations are the grist upon which human selective
breeding grinds. Once a new characteristic is established, these variations
persist from generation to generation, and are systematically and predictably
passed from parent to child. Again, all but the most radical creationists
accepts these facts, widely employed since the birth of animal husbandry
and agriculture  . Third, he recognized that Nature, through selective
pressures like environmental shifts or changes in predation, can play
the role of humans in selective breeding. Whether man selects a long-haired
dog for its appearance, or colder winters favor the survival of thick
furred over short-haired canines, the result is identical. Again, the
power of evolution by Natural Selection is confirmed though field work
(such as Darwin's finches), genetic mapping, and the experience of anyone
who chooses to listen openly to nature.
everyone agrees that, while changes within a species are indisputable
and can be observed within a lifetime, no one has ever seen (nor is
there a recorded observation after 5000 years of written history) one
species transmuting to another. Fish never become fowl, insects never
become birds, and monkeys certainly never become humans.
all this agreement on Darwin's four key tenets, why is there so much
fuss about evolution? Ah, but for one small, annoying small point. Modern
scientists, following Darwin's last great insight, have proven an accumulation
of small changes can lead to an entirely new species, given sufficient
time. Creationists deny there is either enough time (i.e. the Earth
is only a few thousand years old according to one biblical interpretation),
or small changes can never accumulate into a species sized change. Thus,
the argument is not over the Evolution of a species by Natural Selection,
but the Transmutation between species under any circumstances,
including Natural Selection.
evidence for species-changing evolution was already quite strong in
the time of Darwin, but indirect. Now, with the advent of DNA mapping,
we can clearly read evolution's history in our genes, and track genetic
change and reuse from 4 billion-year-old strains of bacteria to their
expression of proteins in modern humans. Yet we still have never seen
a species transform.
my prediction. Based on our growing understanding of genetic coding,
gene switching, protein unfolding and new observational tools, sometime
in the next 25 years one species will be observed to transform into
another. And back again- it will be a simple, single mutation which
triggers the change. If one had to guess, an insect is the perfect candidate-
many already "transmute" from caterpillar to butterfly. Such
an observation would solidify Darwin's Law of Evolution's place among
the greatest of all scientific insights. Reproducible species transmutation
will not convince a creationist of Darwin's validity- loose thinking
and bad science provide a convenient escape clause. But most of us can
finally concentrate on the future rather than debating the past. And
let science and religion coexist in their own, compelling dominions.
Origin Of Species By Means of Natural Selection, Or The Preservation
of Favoured Races In The Struggle For Life- Charles Darwin, 1859
of Man, Charles Darwin, 1871
Religious group vary in their opinions over evolution nearly as much as
they do over their interpretations of scripture (clearly, God either mumbles
when he speaks, or we are hard of hearing, for no two groups receive the
same message from one God). Pope John Paul declared evolution is not in
conflict with the teaching of the Bible or the Church, and left its validity
to be decided by the tools and methods of science (although in July 05,
Pope Benedict XVI seems poised to undermine this interpretation). The
Episcopalians generally are comfortable with an "old earth"
and Darwinism, and see the mechanism of evolution as being set in motion
by God to keep order in his world. Reformed Jews generally agree with
Darwinism, though they lack a central authority on which to rely. The
Dali Lama finds no contradictions between science and Buddhism. Conversely,
most Evangelical Christian groups reject Darwinism as a threat to their
adamant belief in a young Earth and biblical inerrancy.
An Hypothesis is an informed speculation offered to explain a set
of physical observations. A Theory is a hypothesis that has been
experimentally tested and pretty soundly confirmed. A Law
is a Theory so well confirmed and so widely accepted, that no reputable
scientist doubts its truth. Indeed, we are so comfortable with the accuracy
of that law, that we use it to prove or disprove other hypothesis. By
these definitions, Darwinian Evolution lays somewhere between a theory
and a law. On the other hand, Intelligent Design is a hypothesis that
failed as a theory, since it makes no testable predictions, and its attacks
on Darwinism are shallow and easily dismissed. In fact, Astrology
is a much strong hypothesis than Intelligent design, since it makes numerous,
easily tested predictions about fate, love and the probability of individual
actions. Of course, when these predictions are tested, they are no more
accurate than chance. But at least Astrology comes close to meeting
the requirements of a scientific theory. Intelligent design is dumber
than a box of rocks.
August 2005 the President seemed to indicate he supported teaching
"Intelligent Design" along side evolution. Many scientific societies
quickly pointed out he confused dogma with science-
read their considered and sensible positions here.
 Many creationists insist Darwinian evolution is impossible, because the accumulation of small random mutations would never accidentally align in perfect synchrony to produce a wing, or an eye, or life itself. In this they are absolutely correct- complex life is probabilistically improbable. But it's also an irrelevant argument- because Darwin never claimed evolution is random. (Think about it- how likely is it that Darwin and the tens of thousands of scientists following in his footsteps, would make such a trivial calculational error?) Instead, Darwin realized natural selection FAVORS those mutations which increase the chance of survival. Procreation by natural selection is hardly a random process- indeed, it is brutally discriminating. In the previous example, cold weather systematically favored the survival of long-haired dogs from year to year, because the short-haired dogs die off every winter. With only random procreation, neither outcome is favored, and evolution is slowed to a stop. On the other hand, with Darwinian selection after a few generations long hair dogs always outnumber short haired- despite the long odds against this "unlikely" outcome. (see this article for an amazing example of rapid evolution in crickets after a new predator was introduced).
Random mutations- YES, Random evolution- NO.
He also realized, through the study of comparative zoology (now exquisitely confirmed by DNA analysis) that small, likely mutations can drag along large, seemingly improbable changes. For example, a single mutation might tell an insect to make 10 legs instead of 2 by just replaying the leg "program" eight more times (compared to the astronomically unlikely process of thousands of small mutations transitioning smoothly between two and three legs, creating structures of no intermediate survival value). It's as if a mason building a two foot long garden wall simply misread the number "2" on his work order as a "10". So he builds a ten foot long wall without bothering to redraw his plan detailing the placement of thousands of individual bricks. One mutation instead of thousands. Nature constantly re-uses and re-purposes old designs in new environments- just as Darwin predicted.
When you hear a Creationist use words like "random", "unlikely", "intermediate forms" and so on, they are sowing confusion by arguing against a theory completely unrelated to Darwinian Evolution. Perhaps they never bothered to read and learn about the actual science of evolution. In this case they are merely ignorant. If they know the truth and choose to ignore it, then they are simply lying to pursue their own agenda.
 Note added in November 2010: Recent studies have demonstrated that snails can mutate into slugs (i.e. no shells) in one generation through embryonic exposure to platinum. Not yet full proof of a species change- the resulting slugs do not breed true, but an amazing step along the way.